docs: add jackmisbach as a contributor for security

[allcontributors]

Adds @jackmisbach as a contributor for security.

This was requested by iluwatar in this comment

[skip ci]

[github-actions]

PR Summary

Added jackmisbach as a contributor for security to the All Contributors configuration and README badge/table.

Changes

File	Summary
.all-contributorsrc	Added a new contributor entry for jackmisbach in the All Contributors config, including login, name, avatar_url, profile, and contributions: ["security"].
README.md	Updated the All-Contributors badge to 396 and added jackmisbach's contributor card in the README under the Security section.

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autogenerated by presubmit.ai

[github-actions]

✅ LGTM!

Review Summary

Commits Considered (2)

• deced42: docs: update .all-contributorsrc [skip ci]
• a73c2ff: docs: update README.md [skip ci]

Files Processed (2)

• .all-contributorsrc (1 hunk)
• README.md (2 hunks)

Actionable Comments (0)

Skipped Comments (3)

• .all-contributorsrc [3606-3614]

  maintainability: "Add new contributor entry for all-contributors config."

• README.md [9-9]

  enhancement: "Update All Contributors badge in README."

• README.md [589-589]

  enhancement: "Add jackmisbach to security contributors table in README."